Motivated by the work in [1]}, [2]}, the authors of [3]}, [4]}, [5]}, [6]} search for contributions from a nonspinning subpopulation of BHs in the distributions of \(\chi _{\rm eff}\)  and spin magnitude. Some of this previous work has found support for \(a = 0\)  when using parametric spin distribution models that allow for support at that point [7]}, [8]}, [3]}, [10]}, [11]}.
The results of such inference are strongly model dependent, with the preference for the presence of a non-spinning component depending on the morphology of that component.
We do not confidently recover such a feature as demonstrated in Figure REF . Given the width of the 90% credible interval at low spin magnitudes, we are unable to rule out the presence of this feature. This is consistent with what was found in [6]}, [4]}, [14]}, in which the authors find that there is insufficient data to resolve such a non-spinning subpopulation when employing a parametric spin model with a spike at \(a = 0\) .
